Gun charger



ct. l, 1946.

G. A. GOEPFRICH GUN CHARGER Filed March 4, 1943 2 Sheets-Sheet 2 5yl a@ @y Oct. l, 1946. G. A. GOEPFRICH GUN CHARGER Filed March 4, 1945 Patented Oct. 1, 1946 UNITED STATES PATENT OFFICE',

GUN CHARGER George A. Goepfrich, South Bend, Ind.

Application March 4, 1943, Serial No. 477,975

4 Claims.

This invention relates generally to automatic charging devices for automatic guns, and particularly to automatic charging devices for automatic guns of the typewhere the reloading operation is effected by the expansion of exploded gases in the barrel and behind the projectile.

Guns of this Itype Will not reload in the event a dud cartridge has been inserted into the ring chamber, since there will be no exploding gases to move the breech block rearwardly to eject the red cartridge and insert a fresh cartridge. Accordingly, these guns are ordinarily equipped with a charging cylinder for retracting the breech block thereof `in order to eject the dud cartridge and insert a fresh cartridge in the f'eeclway thereof. The retraction of the breech block ordinarily is accompanied by a small movement of a Sear to hold the breach bloclrin retracted position and allow the fresh cartridge to remain in the feedway ready to be moved forward into the ring chamber upon actuation of the Sear. Since guns of this type are ordinarily located remotely from the operator, as lfor example when mounted in an aircraft, mechanical or electrical means must be provided to actuate the se'ar in order to effect automatic firing of the gun.

Since guns of this type may at times fire explosive projectiles, means must be provided to insure against the insertion of a fresh cartridge into the feedway of such a gun until after the dud cartridge has been ejected, since there would be likelihood that a premature explosion might take place in the breech block of the gun, with the consequent damage to the gun and to the aircraft in which it is mounted. YAs has been explained, since the guns are at times located remotely from ythe pilot, it becomes necessary to provide automatic means for recharging one or more of such guns automatically, at the same time insuring against the possibility of premature explosions. The invention accordingly makes use of novel means including a novel electrical circuit for effecting both manual charging of the guns to make them ready for automatic operation, and automatic charging of the guns whenever necessary once automatic operation has begun.

It is an object of this invention to provide an automatic charging system for gas operated automatic breech loading guns.

Another object is to provide a charging system for manual charging of the guns to make them ready for automatic operation, the manual charging being generally effected by the service crew before the aircraft is engaged in combat.

A further object is to provide an automatic charging. system for guns of the type mentioned above which will employ for operation 'uid supplied by the iuid pressure system. of an aircraft;

A still furtherpbject of the invention is to provide an automatic charging system which, a'ft'er being put into operation, will not require the attention of the pilot.

Yet another object of the invention comprehends the provision of a novel control circuit for one or more of such guns, Said control circuit being adapted to manual charging ofthev guns yduring servicing operations, and to automatic charging of the guns afterr servicing operations have been concluded. f

A feature of the inventionv lies in the provision of automatic cut-cut means for the .charging system should one or more of the' guns become jammed in such a fashion that neither manual no'r automatic charging can be effected.

A still further object of the invention comprehends the inclusion of a novel charging mechanis'ni for one or more of such guns, which will add but little to the weight of the guns, certain of the accessories of the 'gun being readily adaptable to the charging system, thereby decreasing the amount of weight necessary to be added to the aircraft, a very important consideration.

A yet further object is to provide a safety device so that charging can be safely accomplished during night.

These and otherl objects of the invention will be apparent from a study ofthe description hereinafter, reference being had to the drawings which show a preferred embodiment of the invention. It is to be understood, however, that the invention is not limited by the embodiments shown, nor otherwise than by the terms of the claims subjoined. 'e

In the drawingswhich illustrate the invention:

Figure 1 is a fragmentary plan view of a gas operated automatic breech loading gun showing also in plan a charging cylinder mounted along one side thereof;

Figure 2 is a longitudinal enlarged horizontal section of the charging cylinder shown in Figure l;

Figure 3 is a fragmentary elevation View of a pair of guns of the type shown in Figure 1, showing schematically a control circuit for the automatic charging system.

Referring now to Figure 1 there is shown a gun l0 having a breech block casing I2 which has mounted for reclprocation therein a breech block I4. Held bythe breech block casing l2 is an ejector I6 which serves to y throw downwardly spent shells which are removed from the iiring chamber by the retraction of the breech block I4 during normal gun operation.

Integral with the breech block casing I2 is a housing I 8 containing a fiuid motor for retracting .the breech block I4 during manual operation or automatic operation of =the charging system forming this invention. Within the housing I8 is a liner I9 having mounted for reciprocation therein a pistonl 20 which is normally urged tol the right by a return spring 22 guided by a sleeve 24 supported by housing i8. Piston 20 is tted with a skirt 25 which is adapted at times to contact a charging lug 28 formed as a part of the breech block I4 to retract, or move rearwardly,the breech block I4 in .the event that reload'- ing does not take place during normal operation i of the gun. By rearward movement of the charging lug 28, contact is made with a switch actuator f 30, which when moved rearwardly actuates a finger 32 to close a switch 34 mounted at the rear of gun I0. The switch actuator 30 is normally biased to the right by a spring 36, so that it clears the finger 32 to open switch 34when the block I4 is in the forward position. A switch 38 is mounted at the forward end of the charging housing IB and is adapted to close when the piston 20 moves rearwardly as a result of pressure supplied to the housing I 8 at a port 40. Y

Referring now to Figure 3 of the drawings th guns I0 are shown with cylindrical ammunition canisters 42 which supply ammunition to the guns I0, and which are locked into place by a locking device 44.

For supplying uid under pressure to the cha-rging cylinder I8 at port 40 a iiuid pressure system comprising a pump 45, accumulator 45 and a reservoir 48 is provided. For controlling the admis#- sion of iiuid to each charging cylinder I8 a solenoid operated valve 50 is provided.

For supplying energy for the control circuit of the guns I0, and for supplying energy to firing solenoids 52 for operating sears 53 of each gun I0 a source of energy 54 is provided.

To get the system shown in Figure 3 ready for automatic charging the guns I0 must rst be manually charged. Where the guns I0 are mounted in aircraft this is ordinarily accomplished on the ground. The system is so arranged that the armorer may manually charge each gun individually withoutl affecting in any way the other guns of the system.

A combat switch S is provided which for manually controlling the charging of the gun may be closed on a contact 58, and for automatically or manually controlling the charging the gun Vmay be closed on a pair of contacts 60 and 62. However, closing on contact 58 avoids the possibility of accidentally closing a trigger switch 04. With combat switch 56 closed on contact 58 current is passed through a lead 63 to a contact 68 of a manual controlled charging switch T0, which when closed passes current through a lead 72 to a thermal time limit switch 'I4 to the solenoid operated valve 5E! which opens to admituid to the charging housing I8 to retract the breech block I4. It will be noted that when the manual controlled charging switch is closed, the ground circuit for thermal time limit switch 14 is open at a switch arm 16. This will permit the breech block I4 to be held in retracted position for an indefinite period as long as manual controlled charging switch 'I0 is closed.

With the closing of the manual charging switch 10 the breech block I4 is moved toits rearward position and the rear gun switch 34 is closed by the actuator 3S and switch iinger 32. Switch 34 will continue to remain closed even if manual charging switch 1B is opened, since the breech block I4 will be held in retracted position by the sear of gun I0.

A trigger lockout 18 is put into its proper position for automatic charging by completing a circuit that energizes a relay of the trigger lockout 18 through a lead 82 branchingfrom lead 60 and through a lead 84 'to ground through switch arm I5 at manual charging switch 10. Energization of the relay 80 attracts an armature 86 to the left closing upon point 83 at which position it remains even though relay 80 is deenergized. being attracted to the right only when a relay 80 Vis energized, under conditions later to be described.

Thus far has been described the manually controlled charging operation which makes the gun ready for automatic charging. With the breech block I4 in the retracted position a live cartridge supplied by the ammunition canister 42 is placed in position in the feedway ofthe gun I0.

Preliminary to automatic charging, which occurs only when defective ammunition has been supplied to the gun I0 and automatic reloading does not take place, the following operations take place in the circuits shown in Figure 3. With the combat switch 56 in the combat position, or closed on switch points 60 and 52, current is supplied through a lead 92 to the rear gun switch, whence it is passed through a lead 94 to energize a timedelay relay 9B, since the breech block I4 is in the rear position. It may be noted, also, that the same operation takes place when'the combat switch 55 is in the manual chargingeposition or closed on point 53. Energizing time delay relay 96 attracts its armature 98 to left, opening its contact point.

Under normal firing conditions, when the trigger switch 84 is closed the following circuits are made. v

One circuit is through trigger switch 64, through a lead |00 and through a winding |04 of a compound relay |02 and thence to ground. Energizing winding |84 of relay attracts an armature 00 thereof to the left closing its contact point; however, the circuit that is made by closing armature IGB on its contact point is still open at the armature 08 of time delay relay 96.

Closing of trigger switch simultaneously energizes a ring relay |08 through a lead I I0 which branches from lead |60, a lead I I2, through armature 86, thence to ground through a lead I|4 to an armature IIS of a pressure switch relay |I8. Energizing the firing relayv |08 moves its armature |20 to the left to pass current from the lead i'to energize the firing solenoid 52, to actuate the scar of the gun I0. The breech block I4 of the gun will then be released and ring will start and continue automatically as long as the trigger switch 54 is closed. The cycle of reloading and ring the gun being shorter than the unloading period of the time delay relay 96, itcontinues in its energized state,l being given a current impulse each time rear gun switch 34 is closed.

The circuit shown in Figure 3 remains unchanged as long as normal ring of the gun takes place, but if the gun misi'lres the following functions occur: i

Since normal reciprocation of the breech 4block I4 will not occur after misre, the breech block will remain in the forwardV position, thereby breaking the circuit periodically made at the rear gunjswitch 34, thus deenergizing time delay relay 96, permitting its armature to fall to the right on its vcontact point. Current will then be passed from lead 65, through armature |06 of compound relay I 02 (which is energized by winding |04 supplied with current by the lead through lead |22, through armature 08 of time delay relay 96, through a, lead |24 which connects to the lead l2 to the solenoid operated valve 50.

It will be noted that the heater element of thermal time limit switch 'I4 is now carrying current, ground being made through the switch arm 16 of the manual charging switch lil. If current to the solenoid operated valve is on for too long a time, which indicates that the breech block |'4 for some reason cannot be retracted, thermal time limit switch 'I4 is opened.

Means are provided for insuring the completionV of an automatic charging operation, once it has been initiated, regardless whether the trigger switch 64 has in the meantime been opened. A lead |25 branches from lead I2 near the thermal time limit switch 'I4 and is connected to a second winding |28 of the compound relay |02, insuring that the relay is energized as long as the circuit to the solenoid operated valve 50 is closed, regardless of the condition of trigger switch G4.

Simultaneously with the closing of the circuits discussed above which occur upon the failure of reciprocation of the breech block l is the closing yof another circuit, made through a lead |30 branching from lead 'I2 near thermal time limit switch 14, to the relay 90, and thence to ground through a lead |32 and an armature |34 of the pressure switch relay vI I8. Closing of the circuit just described energizes relay 90 of the trigger lockout 'i8 to attract armature 85 to the right to deenergize relay 08 and break the c'n'cuit to the ring solenoid 52. It is now impossible to lire the guns I 0 even though the trigger switch 6|! is closed.

The functions described above occur instantaneously as the armature 98 of time delay relay 06 closes to the right. A fractional part of a second after these functions take place iiuid will ow into charging cylinder I8 and will build up a pressure suliicient to close a pressure switch |36 operated by a pressure sensitive capsule |38. It may be noted that the equivalent is shown in Figure 2, the switch 3d closing as soon as the piston 20 has moved a suflicient distance to the left. Closing of switch |36 energizes the pressure switch relay II 8, attracting armatures I I6 and i345 to the left, thus opening the circuit to relay 9d and opening the circuit through armature 86 of the trigger lockout i8. It may be noted that the armature 86 does not close on Contact 88 when relay 00 is deenergized.

For assisting in getting the circuit ready for normal operation of the gun l0, a case ejection switch |40 is closed when the spent cartridge case is yejected downwardly by the ejector i shown in Figure l. Closing switch M0 energizes relay 80 of trigger lockout 'i3 t0 attract armature B6 to the left to close on contact point 88. This operation would normally energize firing relay |08 when trigger switch 64 is closed, but until the uuid is completely exhausted from the cylinder I3 to the reservoir 4S the pressure actuated switch |33 will remain closed to keep energized pressure switch relay H8 and keep armature ||6 from its Contact, thereby keeping the circuit to ring relay |03 open.

As the breech block I4 reaches itsv retracted position rear gun switch 34 will be closed, thereby energizing time delay relay 96, thus opening the circuit to solenoid operated valve 50, which then will operate to connect cylinder I8 to the reservoir 4B, permitting spring 22 to return piston 20 to its starting position. When .the fluid is completely dissipated from cylinder I3, pressure switch |36 will open to 4cleenergize pressure switch relay IIS to permit armatures I|5 and |34 to close on their contact points.

The electrical system may be divided into two circuits. The first circuit comprises a battery ,54, switch 56, wire $6, armature or switch |20, firing solenoid 52, wire 92, relays and HB, pressure switch |36, ejection switch |40, switch 14, solenoid valve 50, relay 90,l wire |32, armature |34, wire |26, and winding |228 of compoundrelay |02. The second circuit comprises the source or battery 54, switch 55, switch 64, Wire |00, wire H0, relay |08, wire |.|2, armature 86, wire |.|4, armature IIS, and winding |03 of compound relay |02.

As an alternate construction, the switch 38 of Figure l is adapted to open when piston 20 reaches its starting position, in the same manne deenergizing relay I I8 as in Figure 3.

If the trigger switch 64 has been opened dur'- ing the automatic charging operation just described, the ring solenoids will, of course, be deenergized, and the Sear 0f gun I0 will hold breech block I4 in retracted position ready to be released when the sear is actuated by the closing of trigger switch 54.

If the triggerswitch 64 has been held closed during the automatic charging operation the breech 'clock will snap forward with a fresh cartridge and will thereafter reciprocate during normal gun operation until for some reason an automatic charging cycle must once more be initiated.

While the circuit has been described as applied to one gun it is equally as well applied to two guns as shown in Figure l, and as shown is, if desired, under the control of a single trigger switch.

The invention has been described in terms of a desirable embodiment thereof, but it is t0 be understood that the invention is not limited by the embodiment shown and described, nor other- Wise than by the appended claims.

I claim:

l. In combination with a gun having a breech block reciprocable for charging the gun, a iiuid pressure motor mounted on the gun and constructed and arranged to engage the breech block to move the same to a retracted position and then release it for countermovement, an electrical system comprising a iirstI and a second circuitV connected to a source of current, an electri cally operated Valve in the iirst circuit for controlling iuid to. the motor and connected in the iirst circuitJ through an openable connection, a time delay relay in the first circuit constructed andarranged to respond to normal reciprocation of the breech block to open said openable connection and to respond to abnormal reciprocation of the breech block to permit closing of said openable connection, a switch in the irstY circuit normally open and constructed and arranged to be closed by the breech block when in a retracted position to connect the time delay relay in the first circuit, a normally open trigger switch in the second circuit, a ring mechanism in the iirst circuit and mounted on the gun for holding the breech block in a retracted position to be released at a predetermined time, said mechanism being -connected in the first circuit through a normally open connection, a relay in the second vcircuit constructed and arranged to respond to closing of the `triggerswitch for closing said normally open connection to said mechanism to cause release of the said breech block, said relay being connected in said second circuit through an openable connection, a relay in the rst circuit constructed and arranged to open said openable connection to said relay in the second circuit to vprevent connecting the firing mechanism in the iirst circuit before the fluid in the iluid motor has been completely exhausted to allow the breech block to return rto its normal firing position, and a switch in the rst circuit constructed and-arranged to respond to fluid pressure in the motor for connecting the last mentioned relay in theiirst circuit to said circuit.

Y 2. In combination with a gun having a breech block reciprocable for charging the gun, a' fluid pressure motor mounted on the gun and constructed and arranged to engage the breech block to move the same to a retracted position and then release it for countermovement, an electrical system comprising a iirst and a second circuit conl nected toa source of current, an electrically operated valve in the rst circuit for controlling uid to the motor and connected in the irst ciro cuit through two openable connections in series, a time delay relay in the first circuit constructed and arranged to respond to normal reciprocation of the breech block to open one of said two openable connections and to respond to' abnormal reciprocation of the breech blockyto permit closing of said one openable'connection, a switch in the rst circuit normally open and constructed and arranged tc be closed by the breech block when in a retracted position to connect the time delay relay in the rst circuit, a normally open trigger switch. in the second circuit, a iiring mechanism in the first circuit and mounted on the gun for holding the breech block in a retracted position to be released at a predetermined time, said mechanism being connected in the iirst circuit through a normally cpen connection, a relay in the second circuit constructed and arranged to respond to closing of the trigger switch for closing said normally open connection to said mechanism to cause release of the said breech block, said relay being connected in Said secondcircuit lthrough an openable connection, a relay in the nrst circuit constructed and arranged to open said openable connection to said relay in the second circuit to prevent `connecting the firing mechanism to the first circuit before the fluid in the fluid motor has been completely exhausted to allow the breech block to return to its normal liring position, a switch in the rst circuit constructed and arranged to respond to fluid pressure in the motor for connecting the last mentioned relay in the first circuit to said circuit, and a compound relay in the rst and second circuits and constructed and arranged to con-1 trol the other of said two openable connections in the first circuit, said compound relay being connected in the second circuit through the trig- 'ger switch during normal gun operation, to close said other openable connection, and connected in the rst circuit through said two openable connections during charging of the gun, whereby a charging cycle once initiated will be completed irrespective of the position of the trigger switch.

3. In combination with a gun having a breech block recprocable for charging the gun, a fluid pressure motor mounted on the gun and con- 8 structed and arranged to engage the breech block to move the same to a retracted position and then release it for countermovement, an electrical system comprising a iirst and a second circuit connected to a source of current, an electrically operated valve in the iirst circuit for controlling fluid to the motor and connected in the rst circuit through two cpenable connections in series, a time delay relay intheV first circuit constructed and arranged to respond to normal reciprocation of the breech block to open one of said two openable connections and to respond to abnormal reciprocation of the breech block to permit closing e of said one openable connection, a switch in the nrst circuit normally open and constructed and arranged to be closed by the breech block when in a retracted position to connect the timev delay relay in the rst circuit, a normally open trigger switch in the second circuit, a firing mechanism in the rst circuit and mounted on the gun for holding the breech block in a retracted position to be. released at a predetermined time, said mechanism being connected in the first circuit through a normally open connection, a relay in the second circuit constructed and arranged to respond to closing the trigger switch for closing said normally open connection to Said mechanism to cause release of the Asaid breech block,

said relay being connected in said second circuit through an openable connection, a relay in the rst circuit constructed and arranged'to open said openable connection tc said relay in the second circuit to prevent connecting the firing mechanism to the rst circuit before the fluid in the iluid motor has been completely exhausted to allow the breech block to return to its normal ring position, a switch in the rst circuit constructed and arranged to respond to duid pressure in the mo-tor for connecting the last mentioned relay in the iirst circuit to said circuit, a compound relay in the -rst and second circuits and constructed and arranged to control the other of said two openable connections in the rst circuit, said compound relay being connected in the second circuit through the trigger switch during normal gun operation, to close said other openable connection, and connected in the rst circuit through said two openable connections during charging of the gun, so that a charging cycle once initiated will be completed irrespective of the position of the trigger switch, and a trigger lock-out mechanism in the first circuit and constructed and arranged therein to disconnect the relay in the second circuit therefrom during a charging cycle and to reconnect said relay in the Second circuit when charging is completed, whereby said ring mechanism is rendered inoperative at times of charging.

4. In combination with a gun having a breech block reciprocable for charging the gun, a fluid pressure motor mounted on the gun and constructed and arranged to engage the breech block to move the same to a retracted position ,and then release it for countermovement, an

electrical system comprising a rst and a second circuit connected to a source of current, an electrically operated valve in the first circuit for controlling uid to the motor and connected in the first circuit through two openable connections in series, a time delay relay in the first circuit constructed and arranged to respond to normal reciprocation of the breech yblock to open one of said two openable connections and to respond to abnormal reciprocation of the breech block to permit closing of said one openable connection,

a switch in the first circuit normally open and constructed and arranged to be closed by the breech block when in a retracted position to connect the time delay relay in the iirst circuit, a normally open trigger switch in the second circuit, a iiring mechanism in the iirst circuit and mounted on the gun for holding the breech block in a retracted position to be released at a predetermined time, said mechanism being connected in the rst circuit through a normally open connection, a relay in the second circuit constructed and arranged to respond to closing the trigger switch for closing said normally open connection to said mechanism to cause release of the said breech block, said relay being connected in said second circuit through an openable connection, a relay in the lirst circuit constructed and arranged to open said openable connection to said relay in the second circuit to prevent connecting the ring mechanism to the rst circuit before the fluid in the fluid motor has been completely exhausted to allow the breech block to return to its normal firing position, a switch in the rst circuit constructed and arranged to respond to fluid pressure in the motor for connecting the last mentioned relay in the rst circuit to said circuit, a compound relay in the rst and second circuits and constructed and arranged to control the other of said two openable connections in the first circuit, said compound relay being connected in the second circuit through the trigger switch during normal gun operation, to close said other openable connection, and connected in the rst circuit through said two openable connections during charging of the gun so that a charging cycle once initiated will be completed irrespective of the position of the trigger switch, a trigger lockout mechanism in the first circuit and constructed and arranged therein to disconnect the relay in the second circuit therefrom during a charging cycle and to reconnect said relay in the second circuit when charging is completed, to render said firing mechanism inoperative at times of charging, and means in the rst circuit for manually controlling charging of the gun, said means being constructed and arranged in the rst circuit to connect the electrically operated Valve in the rst circuit to control iiuid to the motor and to connect the trigger lock-out mechanism in the rst circuit, whereby the gun and electrical system are put in order for normal gun operation and for automatic charging.

GEORGE A. GOEPFRICH. 

